Science fiction often features hokey religions, ancient weapons, and plenty of other very fun concepts that aren't super believable.
But where some sci-fi is more 'fi' than 'sci', hard science fiction is grounded in scientific realism. These are nine of our favorite hard sci-fi movies that you can stream right now, each of which marries compelling stories with fascinating details and accurate information.
2001: A Space Odyssey (1969)
After finding a strange artifact buried on the moon, a team of scientists and astronauts try to trace its origins.
This classic Stanley Kubrick film, which was written simultaneously with Arthur C. Clarke's companion novel, is an impressively accurate depiction of space travel.
Many of the details match up with reality, from the position of satellites, to the centrifugal propulsion, to the trying duration and eerie quiet of space travel.
Released more than 50 years ago, 2001: A Space Odyssey raised the bar for hard sci-fi movies to come.
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The Martian (2015)
The Martian is based on a novel of the same name by Andy Weir, and follows Mark Watney, an astronaut left behind on Mars. While he waits for a rescue mission, he is forced to innovate in order to survive.
NASA provided their expertise to help the production replicate accurate equipment for the spacecraft and the astronauts. They also offered images and information about Mars to help the movie capture Martian scenery and conditions in a realistic manner.
Additionally, many major plot points hold up to scrutiny, like the possibility of restoring prior NASA equipment to communicate back to Earth; growing sustenance on Mars to survive; and traveling between planets on a realistic time frame.
Related: 13 Thrilling Space Movies That Explore the Final Frontier
Gattaca (1997)
In the future of Gattaca, parents can curate the genetic characteristics of their babies in laboratories using cutting-edge sciece.
Children conceived outside of these laboratories are labelled “invalids,” and considered inferior. Gattaca centers on Vincent Freeman, an “invalid” who is determined to become an astronaut despite the discrimination he faces.
The jarring premise of Gattaca is firmly grounded in scientific capabilities that are close at hand.
Genome sequencing has become much more advanced, and many in the scientific community are debating the morality of using genetic modifications in a variety of applications, from preventing diseases, to designing babies.
Deep Impact (1998)
In Deep Impact, a comet is set to collide with Earth, and the American government has instituted a series of contingency plans. While they hope to detonate the asteroid and avoid catastrophe, they have also selected a limited number of American to survive in bunkers in a worst-case scenario.
Deep Impact has been commended for its scientific plausibility. For instance, NASA is developing plans to deflect potentially-dangerous asteroids.
And while the movie's inciting event – an amateur's discovery of a potentially humanity-ending comet –may seem unlikely, many discoveries in astronomy over the decades have come from those exploring the night skies at home.
Andromeda Strain (1971)
When a satellite carrying microscopic organisms crashes in New Mexico, those in the surrounding areas begin to die. Disturbed by the spread of mysterious deaths, the government sends in a team of scientists to investigate.
Andromeda Strain, which is based on Michael Crichton's novel of the same name, remains grounded in real-life epidemiology. Extraterrestrial pathogens could potentially survive aboard space crafts or equipment, and NASA takes precautionary measures to prevent outbreaks.
RELATED: Alarming Books About Plagues
Contact (1997)
Based on the novel of the same name by Carl Sagan, a legend in all things space, Contact follows a Search for Extraterrestrial Intelligence (SETI) scientist who makes contact with extraterrestrials through a series of radio waves. She communicates with these lifeforms by crafting a mathematically-based message.
This is a spot-on portrayal of how a human-extraterrestrial exchange might occur, given that SETI is a real-life organization that works to discover extraterrestrial life forms, and often analyzes radio waves intercepted from space to do so.
In 1974, SETI scientists even tried to communicate with aliens via a radio message transmitted from SETI's Arecibo Observatory.
RELATED: Powerful Books About Alien Contact and Messages from Outer Space
Minority Report (2002)
Set in 2054, this futuristic chase thriller centers on a team of special officers who are part of the PreCrime division, tasked with detecting future crimes and preventing them before they occur.
While the movie sparks a debate about determinism and free will, and raises questions about the government’s involvement in private lives, its depiction of future technologies was strikingly accurate.
In the process of making the movie, director Stephen Spielberg collaborated with prominent experts to craft a realistic portrayal of the future. Many of the devices Spielberg incorporated into the film now exist.
Minority Report included technologies with gesture recognition, retinal scanners, self-driving cars, virtual reality systems, personalized ads, and motion tracking computers – all of which are familiar to us today.
Related: The 5 Coolest Technologies from Hard Science Fiction
Her (2013)
Her tells the story of an introverted man who falls in love with an artificially intelligent operating system named Samantha.
The award-winning movies stretches the scope of technology and artificial intelligence beyond its current limits, but still provides a likely portrayal of AI technology that may be available in the near future.
After all, we already talk to artificial intelligence devices that assist us in tasks. Though these technologies are not yet as emotionally intuitive or lifelike as Samantha in Her, we can determine their settings and adjust them to our preferences.
Arrival (2016)
In Arrival, linguist Dr. Louise Banks is called upon to communicate with alien lifeforms that have appeared in crafts in twelve different countries. Their sudden arrival alarms governments across the globe, and as the situation escalates, Dr. Banks races to discover the purpose of their presence on Earth.
To communicate with the extraterrestrials, Dr. Banks acts out different words, which the aliens respond to in their corresponding symbol. Building up a vocabulary of basic terms, Banks pushes for more information. Languages are often translated in this manner, by creating a shared understanding of essential terms and the way each respective language represents them.
As Dr. Banks' knowledge of the alien language evolves, her perception of time, and capacity for temporal thinking, shifts to match the aliens'. This depicts a scientific concept known as linguistic relativity, or the Sapir-Whorf hypothesis.
Linguistic relativity poses that one’s language can influence cognitive function and cultural understanding – a phenomenon Dr. Banks experiences.
Related: The 6 Best Alien Movies Like Arrival
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